


Beefcake Sensei: The Beginnings

by mandapandabug



Series: Beefcake Sensei [1]
Category: Naruto
Genre: BAMF Umino Iruka, M/M, Pining Hatake Kakashi, beefcake Iruka
Language: English
Status: Completed
Published: 2021-01-26
Updated: 2021-01-26
Packaged: 2021-03-18 15:54:39
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,458
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28994793
Author URL: https://archiveofourown.org/users/mandapandabug/pseuds/mandapandabug
Summary: Naruto has let out a strange fact about his favorite sensei. Iruka weighs a lot more than he looks. What is the sensei hiding under his baggy uniform? Kakashi certainly wants to know, and he'll show up on time to find out!
Relationships: Hatake Kakashi/Umino Iruka
Series: Beefcake Sensei [1]
Series URL: https://archiveofourown.org/series/2128008
Comments: 14
Kudos: 174





	Beefcake Sensei: The Beginnings

**Author's Note:**

> Another little one-shot plot bunny that got me! This was inspired by the Umino Hours Discord. When you talk about beefcake sensei, what else can you expect?!  
> Just a light warning, this talks about weight, and I wouldn't categorize it as shaming, but I just want to warn y'all! :) Also there is a lot of sexual tension but nothing actually happens so... Rated Teen...  
> Disclaimer: I don't make money from this or own Naruto... Parody is free!! haha.  
> Please don't mind my crazy, hope you enjoy!

“Naruto, get off me! You’re heavy. Probably all the rocks in your head.” Sakura yelled at Naruto, who had dramatically fallen onto her as they were sparing with Yamato-sensei. She whapped him over the head for good measure.

Naruto huffed, rubbing the lump on his crown. “You think I’m heavy? Have you tried to lift Iruka-sensei?! It’s like a whole elephant in a tiny package!” Naruto exclaimed waving his arms around like a loon.

“That’s not very nice, Naruto.” Sakura said, she was sensitive about her own weight, and didn’t really like what Naruto was implying about their kind ex-sensei.

“Well, it’s true. I only tried to help him up one time and it was like lifting a boulder.” Naruto pouted, clearly not getting why he was being offensive.

“Hmm, he didn’t look very large from what I recall.” Sai added, completely unaffected by the bickering, but at least trying to engage in more comradery.

Kakashi leaned into the conversation, clearly interested, but not willing to contribute just yet. He was always listening for a tidbit on Iruka and Naruto was the best source he had.

“Well, how much does he really weigh? I mean, you aren’t very strong Naruto, maybe it’s just you being a weakling.” Sai casually insulted, it was as plausible a reason as any other.

“We could always check,” Kakashi blurted out, fully invested in this plot.

“Yeah! He’s heavy I swear! Let’s look in the record room! That kind of info is in the public records after all.” Naruto said excitedly.

“How do you know that, hmm? Who have you been stalking?” Kakashi knew the reason the brats knew about the records rooms, from when they tried looking to see his face without the mask. He even helped them as his alter-ego, Sukea. It was a good time all around, and it had made his students work together, so maybe a repeat lesson was in order with Sai. They needed some team building activities that weren’t dramatic missions.

Naruto and Sakura look embarrassed since they didn’t know Kakashi knew about their time with Sukea.

“No… n… nothing, no one, I mean no how… I mean. Nothing!” Naruto would never make it in espionage.

“It’s common knowledge, Kakashi-sensei,” Sakura said more coolly. Kakashi was proud of her for keeping a better façade.

“We aren’t getting any more training done, are we?” Yamato said exasperated. He wasn’t a fan of invasions of privacy, but they were ninja and Kakashi’s secret crush was anything but secret. If it involved Iruka, Kakashi butted in.

“Yosh! Let’s go!” Naruto jumped up and led the way to the records room in the Hokage tower.

\--

Genma looked up at Team 7 with a curious eye. He was on duty in the records room organizing scrolls and doing other menial, boring tasks.

“What are you lot up to?” Genma was suspicious of the large group entering the normally empty space. Maybe something interesting would happen today. He would take any excuse to break the monotony. Tsunade was cruel indeed with this assignment. All he did was get caught staring at her ample breasts. But really, they are just so round and out there! What was he to do?

“We want to see how much Iruka-sensei weighs,” Naruto minced no words. The rest of the group groaned at his lack of tact but didn’t really, did it matter? If any record room attendant wouldn’t care, it was Genma.

Genma looked confused but followed them into the personal information section of the filing cabinets. This was weird, but much more interesting than his current task.

“Umino, Umino, Umino, a-ha!” Sakura found the file first, “height – 178, weight – 67 kg? That doesn’t seem heavy. It must be similar to any other grown ninja?”

“I am 178 cm tall… I am 58 kg.” Yamato says, face blank as always, but his mind churning.

“What!?” Naruto looked at his new sensei with a scrutinizing eye, “but you look just the same as Iruka. He doesn’t look bigger than you… and by 10 kg almost?”

“Wait, that weight was from three years ago. There is an amendment note here from a physical just last week… 72 kg?!”

“This is getting interesting,” Genma chimed in, “he’s heavier than me, and I’m 3 cm taller…”

“He weighs 3 kg more than me, and I’m the same height as Genma.” Kakashi added lamely, not sure how to take this news. Nothing would stop his heart from puttering harder whenever he was near Iruka, but this was a mystery. How was Iruka hiding the extra bulk?

“Well, you’re a beanpole Kaka-sensei.” Naruto teased, attempting to pinch Kakashi’s side, but the jōnin easily side-stepped and Naruto somehow fell over at the sudden lack of body.

“Interesting, he doesn’t look big, but he weighs more than all of you…” Sai assessed, he wasn’t actually very invested in this (having never officially met the famous Iruka-sensei), but it seemed his comrades were, and he wanted to get closer to them.

“I have never seen him out of uniform before, maybe it’s an optical illusion! His uniform is always really big, it makes him seem smaller. He gained 5 kg while I was away. I hope he wasn’t depressed without me. Eating ramen all alone, every day…” Naruto tried to logic out some reason as to how he missed how much weight his sensei had gained and why.

“I don’t recall, it’s been awhile since I’ve really looked at Iruka-sensei. And 72 kg isn’t that heavy really.” Sakura tried to make the men be a little more aware of the potentially sensitive subject.

“Well, let’s turn this into a training exercise.” Kakashi said, eyebrow wiggling. He could kill two birds with one kunai: spy on Iruka (one of his favorite pastimes) and get some stealth training in for his students.

“That doesn’t sound like a good use of time, Kakashi-sempai.” Yamato did not endorse this as a good use of training time. He was technically the jōnin leader of team 7 now and he should get to decide. He was clearly vetoed since Naruto, Sakura, Genma, and Kakashi were already out the door heading toward the academy.

\--

Naruto was the boldest, as usual, and walked right up to Iruka as he was watching the new pre-genin practice their kunai aim. He had a tape-measure behind his back as he snuck up on Iruka from behind.

“Iruka-sensei!” Naruto yelled as he leapt toward the teacher. He was attempting to wrap his arms around Iruka in a hug (and use the measuring tape to get Iruka’s waistline), but he startled the chūnin and Iruka instinctively back kicked Naruto before he even got close.

Naruto went flying through the yard.

“Naruto!” Iruka said when he turned to see who he kicked and rushed over to Naruto gasping on the ground 10 feet away. “I’m so sorry, Naruto, but you startled me! What were you doing?”

Iruka was leaning over, hands on his knees, in front of Naruto. Kakashi was thoroughly enjoying the view from behind Iruka. Kakashi could confirm his butt looked just as round, tight, and perfect as always. Kakashi resisted relaying this information to his team and just continued to watch the show.

“Iruka-sensei!” Sakura came out of no where as well, but Iruka was more prepared this time, and just turned to greet his former student.

“Sakura-chan! How is my smartest student doing?” Iruka flashed a charming smile to Sakura and the teen blushed.

Kakashi tried to keep his jealousy in check as he suddenly appeared next to Sakura. “Hello, Iruka-sensei, how are you this fine afternoon?” Kakashi grinned behind his mask.

“Kakashi-sensei, what are you and your team doing here?” Iruka asked suspiciously.

“Not everyone is here, Iruka-sensei.” Naruto said, gasping just a little for breath.

Iruka gave Naruto and the rest of them an incredulous look. “Sai and Yamato-sensei are in the bushes. Were you trying to hide?”

Sai and Yamato gave each other a surprised look before walking up to the group, pretending they meant to be in the bushes, very embarrassed at being discovered.

“OK… What are you all doing here?” Iruka asked, trying to keep an eye on his kids while the entirety of team 7 was in his school yard. He put his hands on his hips as he toggled his eyes between the strange team and his precious new students.

“Iruka-sensei, I just missed you.” Naruto said, wrapping his arms around Iruka’s waist this time.

“Naruto…” Iruka was shocked. Naruto was only a little shorter than him, but he was hugging him low, around his waist, face smooshed into Iruka’s chest.

In this position, Iruka couldn’t hug Naruto back, so he just patted the teen on the back.

“OK, well, see ya!” Naruto suddenly let go, leapt away from Iruka, and sprinted away.

Iruka turned to the other members of Team 7. “What in the world?”

“See ya, Iruka-sensei!’ Sakura grabbed Sai and made a break for it.

Yamato looked at Kakashi, then back at the dust trailing after his students, and finally to Iruka, “good day, Iruka-sensei.” Yamato looked to Kakashi, trying to draw his eye. However, Kakashi was staring at Iruka, his cocked to the side with an adorably confused face, he looked like a little nin-kin puppy.

Iruka shook his head and walked back to his students, who were luckily not filleted.

Yamato grabbed Kakashi’s elbow and dragged him after their own students.

\--

“What did you discover, Naruto?” Kakashi and Yamato approached just as Genma started interrogating Naruto.

“How did Iruka-sensei not notice you, Genma-san?! How did he notice Yamato-sensei and Sai and not you?” Sakura asked staring very intently at the village gossip.

“Oh, you think this is the first time I’ve had to spy on Iruka for a juicy bit of gossip?! I learned my lesson the first time.” Genma rubbed the back of his head, lost in a painful memory.

“I got the info guys!” Naruto held up the tape measure with a victorious smile flashing across his face.

“Well, what is it?” Genma said impatiently.

“Umm… I wrapped this around him and… it went to about… here?” Naruto held the tape measure up at 110 cm.

The surrounding ninja sighed. “Naruto, clearly, your arms fit around him comfortably. He isn’t over 100 cm wide.” Kakashi rolled his eye at his student, this lesson was not turning out well.

“Oh… well yeah… His chest was really hard when I was hugging him though. He has been eating a lot of ramen with me lately, so maybe he’s just so bloated from the salt?”

“Well, this won’t do. We need to catch him without the clothes.” Sai said, catching Kakashi’s ear.

“No, no Sai, that isn’t normal.” Yamato sighed, rubbing his hand over his eyes exasperated.

“Now, now, now, Tenzō-kohai, let’s not dismiss the idea so quickly.” Kakashi said trying to use his stupid genius brain to come up with some way to get Iruka to take his clothes off. For the lesson.

“Eternal rival!” Gai spun into view seemingly out of nowhere, Sakura and Naruto looked shocked, but the jōnin were all cool as cucumbers, clearly use to Gai’s antics. “I heard you were trying to get clothes off?! Oh, the springtime of youth! Showing off our years of hard training. I will challenge you to-“

“Gai-sensei, when did you show up?” Kakashi interrupted coldly.

“So cool,” Gai whispered, tears streaming down his face.

“Gai-sensei, do you think you can get Iruka out training?” Naruto said, hoping to get an ally who Iruka wouldn’t suspect of foul play. Kakashi was impressed, he didn’t think Naruto would be clever enough to think of such a scheme.

“If this is a challenge, then it is one I have already won!” Gai spun into his nice-guy pose, teeth flashing brightly. “I already train with Iruka-sensei. We do laps in the lake every other morning.”

“Oh, so he’s working out again? It’s probably since I’m back. I’m happy you’re helping him out of his funk, Bushiest Brow-sensei.” Naruto nodded, convinced now that the added weight was due to his depression from missing Naruto.

“Umm, well, if you all want to come and train too, we start at dawn tomorrow. You can witness me winning the challenge before you even had a chance, worthy, yet beaten rival!” Gai ran off at that, clearly, he was in the middle of some training with his own team because Lee, Ten-Ten, and Neji appeared moments later asking if they had seen Gai-sensei anywhere and if so, what way he had gone.

They all pointed in the vague direction Gai sashayed in.

“So, I guess we meet again at dawn. Should be around 5:30. I’ll be there. If it’s swimming, we will get to see just what’s up with Iruka-sensei.” Genma said before disappearing, he had been away from work for too long and Tsunade couldn’t find out he had played hooky. Once he had good gossip maybe he could get back on her good side.

“This seems really invasive,” Sakura said looking at each of the members of Team 7 in turn. None of them looked like they agreed except Yamato. “Yamato-sensei, you agree, right? This is mean spirited.”

“Well, I need to confirm Gai won the bet, so I’ll be there.” Kakashi said as he body flickered away as well. Yamato knew it was just an excuse to hopefully get to see Iruka shirtless and dripping wet. He rolled his eyes at his stupid Sempai and his stupid crush.

Yamato sighed; this was going to be the hardest assignment he would ever face wouldn’t it? “I’m sorry Sakura, but we should probably show up and wrangle the others into some tact.” Sakura nodded. It was accurate. Naruto was in his head probably thinking of a million things to tell Iruka and who knew what Kakashi would say. The man was odd at the best of times. Sakura and Yamato were the only shot of keeping Iruka from being completely embarrassed and the others from facing his unending wrath.

\--

Sakura arrived at the lake precisely at 5:30. Yamato, Genma, Sai, and Naruto were already there. She wasn’t surprised that Kakashi was nowhere to be seen.

She could barely make out the forms of Gai and Iruka in the water, swimming at an incredible pace back and forth.

“They have been going for half an hour at least.” Naruto said in shock.

“They aren’t using any chakra.” Genma said in shock.

“I’m not sure they have taken even one breath.” Yamato said in shock.

“They have gone through every kind if stroke perfectly.” Sai said in shock.

Sakura let out a shocked gasp of her own as Kakashi appeared next to her, only a minute late. “So, you can be on time?!” Sakura yelled. Her yell dried up immediately as Gai and Iruka got out the water.

Sakura gapped like a fish, flush blotching her face in patches of red. She looked over at the other ninja’s gathered in the early morning dusk. Kakashi was bright red on the quarter of his visible face, eye tracing down Iruka’s form. Yamato had his strange dead facial expression on, but there was unmistakable red coloring the tips of his ears. Naruto’s jaw was on the ground. Sai looked like he was trying to go through complex arithmetic in his head. Genma’s signature senbon was on the ground, his mouth opening and closing seemingly without command.

Iruka was a hunk. He immerged from the lake like an Adonis. His hair was down and the ends dripped perfect little droplets of water down onto his sculpted pectoral muscles. All his muscles were bulging, it was almost obscene.

Sakura tried to remember him as her ex-sensei, kind and humble man he was, but then Iruka lifted his bulky arms up to slick his hair back into a low ponytail and she had to turn away to dab at her bleeding nose.

Kakashi was staring at the pre-genin sensei as he lifted his arms, biceps flexing perfectly, and swiped his hair out of his face. The action brought Kakashi’s eye directly to his perfect abs. There were 8 little hills flawlessly placed on his stomach. The water dripped over and around the muscles, unable to go straight down without having to journey over the rough terrain.

Kakashi was watching one particular drop’s long, arduous journey from where it started at Iruka’s full lips, down the side of his jaw, down his strained neck. It teased down the sensei’s perfect right pec, just missing his pert nipple before it slide over, up and down each ab. Each hillock. Until it met its fate and was absorbed into the speedo just barely covering enough of the sensei to be appropriate.

Kakashi wanted to trace that droplets path with his tongue. He almost did, about to take the first step toward his desire, when he was snapped out of his reverie.

“Iruka-sensei! You’re ripped!!” Naruto seemed to gain himself much faster than anyone else present. It made sense since he probably wouldn’t be lost in lust at the sight of his pseudo older brother.

“Oh…” Iruka dropped his arms, sheepishly folding them across his gorgeous body. Kakashi wanted to tie those arms to his side so he could never hide that perfect body from him again. Then again, the way he folded his arms across his chest and stomach was doing wonders for his swollen deltoids. “I figured that I needed to get a hobby since you weren’t bothering me all the time anymore Naruto. So, I asked Gai if he would train with me. Swimming is really a great workout.”

Kakashi would kill Gai. He made Iruka even more irresistible. Then Gai put his arm around Iruka’s shoulders (his perfect, hard, shoulders), and Kakashi swore Gai was going to lose that arm if he didn’t let go soon.

“Iruka has beaten me in the water every time, he is being humble. I’m lucky to get to train with him!”

“Yes, but you always win on land!” Iruka laughed, and Gai luckily dropped his hold on Iruka because Kakashi was radiating killing intent. Yamato had to elbow him to get him to control it.

Everyone seemed to gather their wits to a degree.

“So, you didn’t get fat and depressed because you missed me, Iruka-sensei?” Naruto asked, teary eyed.

“Naruto!” Iruka looked concerned and confused. “I… well, I was really sad when you left. I decided to start training more to distract myself. I missed you terribly.” Naruto ran to Iruka and hugged him like a normal person would, ignoring the fact that he was getting all wet and that Kakashi was glaring daggers into his back.

“OK!” Kakashi practically screamed. Everyone jolted at the noise. Had they ever heard the cool, hip ninja yell before? “It’s time to train. Clearly we have a long way to go if we are to catch up with Iruka-sensei.” Kakashi purred his name and when Iruka made eye contact with Kakashi for the first time that morning, he could see the leer emanating in his direction.

Iruka cleared his throat and pulled away from Naruto.

“Yes! I will train every day super hard to match my favorite sensei!” Naruto exclaimed and dropped to the ground doing push-ups. Iruka laughed and it wasn’t fair. Kakashi had never seen anything so beautiful before.

Iruka kneeled to get his gear and Kakashi couldn’t stop staring at his thick thighs. There was no part of Iruka that was thin or gangly, just all hard, corded muscles. Kakashi wanted to massage them until they were pliant and then move onto massage another body part until it was hard instead.

“Yes, Kakashi-sempai, we should get going!” Yamato said, grabbing his dumbstruck leader and yanking him out of the training field. Sakura, Sai, and Naruto followed behind the two.

With Kakashi out of the picture, Iruka noticed Genma bending over to pick up his senbon. Iruka smirked at the effect he seemed to have on these jōnin.

“Genma-san, what were you doing with team 7? Is there a mission or something?” Iruka asked innocently.

“Umm… No… I…” Iruka had never heard Genma speechless before, so Iruka just looked on in shock as the jōnin blinked, then body flickered out of the training ground.

“Most unusual morning, eh Iruka?!” Gai said, pulling his jump suit on over his wet body.

“Yeah…” Iruka said, watching the backs of Team 7 as they made their escape. “Strange,” Iruka smiled to himself. So, Kakashi finally noticed him, eh? He would let the elusive man come to him; the bait was set and it looked like he had Kakashi, hook, line, and sinker.


End file.
